ref(device): Share platform mapping helper

Extract device platform string-to-enum mapping into a shared helper used by
build_run_device and get_device_app_path.

This removes duplicated mapping logic while preserving existing behavior and
keeps device tool platform handling consistent in one place.

Author: cameroncooke

src/mcp/tools/device/build-settings.ts

@@ -14,6 +14,23 @@ function resolvePathFromCwd(pathValue?: string): string | undefined {
   return path.resolve(process.cwd(), pathValue);
 }
 
+export type DevicePlatform = 'iOS' | 'watchOS' | 'tvOS' | 'visionOS';
+
+export function mapDevicePlatform(platform?: DevicePlatform): XcodePlatform {
+  switch (platform) {
+    case 'watchOS':
+      return XcodePlatform.watchOS;
+    case 'tvOS':
+      return XcodePlatform.tvOS;
+    case 'visionOS':
+      return XcodePlatform.visionOS;
+    case 'iOS':
+    case undefined:
+    default:
+      return XcodePlatform.iOS;
+  }
+}
+
 export function getBuildSettingsDestination(platform: XcodePlatform, deviceId?: string): string {
   if (deviceId) {
     return `platform=${platform},id=${deviceId}`;

src/mcp/tools/device/build_run_device.ts

@@ -23,7 +23,7 @@ import { nullifyEmptyStrings } from '../../../utils/schema-helpers.ts';
 import { extractBundleIdFromAppPath } from '../../../utils/bundle-id.ts';
 import { install_app_deviceLogic } from './install_app_device.ts';
 import { launch_app_deviceLogic } from './launch_app_device.ts';
-import { resolveAppPathFromBuildSettings } from './build-settings.ts';
+import { mapDevicePlatform, resolveAppPathFromBuildSettings } from './build-settings.ts';
 
 const baseSchemaObject = z.object({
   projectPath: z.string().optional().describe('Path to the .xcodeproj file'),
@@ -54,21 +54,6 @@ const buildRunDeviceSchema = z.preprocess(
 
 export type BuildRunDeviceParams = z.infer<typeof buildRunDeviceSchema>;
 
-function mapPlatform(platform?: BuildRunDeviceParams['platform']): XcodePlatform {
-  switch (platform) {
-    case 'watchOS':
-      return XcodePlatform.watchOS;
-    case 'tvOS':
-      return XcodePlatform.tvOS;
-    case 'visionOS':
-      return XcodePlatform.visionOS;
-    case 'iOS':
-    case undefined:
-    default:
-      return XcodePlatform.iOS;
-  }
-}
-
 function extractResponseText(response: ToolResponse): string {
   return String(response.content[0]?.text ?? 'Unknown error');
 }
@@ -94,7 +79,7 @@ export async function build_run_deviceLogic(
   executor: CommandExecutor,
   fileSystemExecutor: FileSystemExecutor = getDefaultFileSystemExecutor(),
 ): Promise<ToolResponse> {
-  const platform = mapPlatform(params.platform);
+  const platform = mapDevicePlatform(params.platform);
 
   const sharedBuildParams: SharedBuildParams = {
     projectPath: params.projectPath,

src/mcp/tools/device/get_device_app_path.ts

@@ -7,7 +7,6 @@
 
 import * as z from 'zod';
 import type { ToolResponse } from '../../../types/common.ts';
-import { XcodePlatform } from '../../../types/common.ts';
 import { log } from '../../../utils/logging/index.ts';
 import { createTextResponse } from '../../../utils/responses/index.ts';
 import type { CommandExecutor } from '../../../utils/execution/index.ts';
@@ -17,7 +16,7 @@ import {
   getSessionAwareToolSchemaShape,
 } from '../../../utils/typed-tool-factory.ts';
 import { nullifyEmptyStrings } from '../../../utils/schema-helpers.ts';
-import { resolveAppPathFromBuildSettings } from './build-settings.ts';
+import { mapDevicePlatform, resolveAppPathFromBuildSettings } from './build-settings.ts';
 
 // Unified schema: XOR between projectPath and workspacePath, sharing common options
 const baseOptions = {
@@ -54,26 +53,11 @@ const publicSchemaObject = baseSchemaObject.omit({
   platform: true,
 } as const);
 
-function mapPlatform(platform?: GetDeviceAppPathParams['platform']): XcodePlatform {
-  switch (platform) {
-    case 'watchOS':
-      return XcodePlatform.watchOS;
-    case 'tvOS':
-      return XcodePlatform.tvOS;
-    case 'visionOS':
-      return XcodePlatform.visionOS;
-    case 'iOS':
-    case undefined:
-    default:
-      return XcodePlatform.iOS;
-  }
-}
-
 export async function get_device_app_pathLogic(
   params: GetDeviceAppPathParams,
   executor: CommandExecutor,
 ): Promise<ToolResponse> {
-  const platform = mapPlatform(params.platform);
+  const platform = mapDevicePlatform(params.platform);
   const configuration = params.configuration ?? 'Debug';
 
   log('info', `Getting app path for scheme ${params.scheme} on platform ${platform}`);